This whole time I thought the AA headers were better than the Euro ones. Thanks for the info. Also, where can I get the euro headers for $500?Yes. SGT, just like fabspeed, AP, evosport, JVT, manzo, topspeed are copies of Supersprint's long tube header (tubulare) which was an upgrade on the standard euro header (and of course a big upgrade on u.s. header with cats). They're all made in china with chinesium. They're heavy and the metal is thick, so slightly smaller ID (slightly less flow) and the sound is a bit muffled. More of a deeper subdued rumble rather than the typical zingy rasp. Most people like the sound these create, out the tail pipe, but from the driver's seat, it sounds lazy to me, more like a v6.
The AA or megan headers are also (cheap) copies, but of the Euro/CSL header. Again, metal is thicker, so heavier, but sound is still pretty close, it retains the rasp.
Both are the smaller size pipes (55mm or 2.16") vs. Supersprint's biggest SSV1s at 63.5mm or 2.5".
Performance wise, the supersprint tubulare design is an upgrade on the csl header, so if the replica is very close, it too should have slightly more umph vs. the AA/Megans. The SS stepped v2s are upgrades on the tubulare and the SSv1 stepped are the best over everything.
At $300 for Megan vs. $700 for SGT or whatever it is, I'd say get AA/megan. My personal opinion is to skip all replicas and get euro headers for $550 or go big with supersprint for $2-3k.
With these replicas, keep in mind that their flanges are thicker and there'll be less stud to get the copper header nuts onto. It's doable, they shouldn't work loose, but it's possible. The supplied gaskets are also too thick, so get new OE ones. Some people go so far as to install longer studs. I'd rather get better headers. get new nuts (x18) no matter what imo.